We are often asked by customers if they can use their lawn sprinkler to water their new evergreen privacy trees we install for them. When it comes to keeping your evergreen trees healthy and hydrated, the method of watering you choose plays a crucial role. While lawn sprinklers are common, they are not the most efficient choice for evergreens. Drip irrigation offers a targeted approach that conserves water and promotes deeper root growth. Targeted water allocation also provides better concentrated fertilization to the roots.
For the Mid-Atlantic region (Maryland, DC, Virginia and West Virginia), our climate has been getting hotter and dryer over the years. This year our Spring has been dryer than normal so watering of evergreens installed within the past 2 years is imperative for them to thrive. Let’s explore the differences between these two methods. In order to get 1-4 gallons at the base of the new tree depending on the size of the tree, the lawn sprinkler would cover a really large area using 300 gallons of water to get 1-4 gallons of water under the tree.
Flow Rate: Precision vs. Volume
- Drip Irrigation: Delivers water slowly and directly to the root zone, typically at rates between 0.5 to 4 gallons per hour per emitter. This slow delivery allows water to seep deeply into the soil, encouraging robust root systems.
- Sprinkler Systems: Operate at higher pressures, distributing water over a broad area. While they can cover large spaces quickly, a significant portion of water can be lost to evaporation and runoff, especially on hot or windy days.
Spray Field: Targeted vs. Broad Coverage
- Drip Irrigation: Applies water directly to the base of each tree, ensuring that moisture reaches the root zone without wetting surrounding areas. This targeted approach reduces weed growth and water waste. Plus, reduced overspray, evaporation and wind drift.
- Sprinkler Systems: Spray water over a wide area, which can lead to uneven watering. Trees may receive water on their foliage rather than at the roots, leading to potential fungal issues and inefficient hydration. As stated above, in order to get 1-4 gallons at the base of the new tree depending on the size of the tree, the lawn sprinkler would cover a really large area, using 300 gallons of water to get 1-4 gallons of water under the tree, which is not an efficient use of water, especially if you are on a well.
Efficiency: Conservation and Tree Health
- Drip Irrigation: Boasts up to 90% water-use efficiency by minimizing evaporation and delivering water where it’s needed most. This method supports deeper root growth, making trees more drought-resistant.
- Sprinkler Systems: Typically achieve 65-75% efficiency, with losses due to evaporation, wind drift, and runoff. Over time, this can lead to higher water bills and less resilient trees. Plus, if you are on a well, it can drain your aquifer more than necessary. Those that choose manual hand watering, the efficiency is only 50-70%, which is no better than a lawn sprinkler.
Detailed Comparative Chart: Drip vs. Sprinkler Irrigation
| Feature | Drip Irrigation | Sprinkler Systems |
|---|---|---|
| Flow Rate | 0.5–4 GPH per emitter | 60–300 GPH per head |
| Water Efficiency | Up to 90% | 65–75% |
| Water Loss | Minimal (<5%) | High (15–40%) |
| Coverage | Targeted at roots | Broad area |
| Weed Growth | Reduced | Increased |
| Disease Risk | Lower | Higher (due to wet foliage) |
| Installation Cost | Moderate | Higher |
| Maintenance | Low | Moderate to High |
Isn’t Rain Enough Water?
On new tree plantings that were installed within the last 2 years in Maryland, DC, Virginia, and West Virginia, relying only on rain is not enough water to wet the root mass of the new trees. The trees need 4 gallons of water every other day from March – November for the first 2 years.
Drip Irrigation is the Superior Choice
For evergreen trees, drip irrigation offers a more efficient and effective watering method compared to traditional sprinklers. By delivering water directly to the roots, it conserves water, reduces weed growth, and promotes healthier, more resilient trees. To reiterate, to achieve 1-4 gallons at the base of the new tree depending on the tree size, the lawn sprinkler would cover a vast area, using 300 gallons of water to deliver 1-4 gallons of water under the tree. While the initial setup of a drip system may require more effort, the long-term benefits for your evergreen trees and the environment are well worth it.
Learn more low maintenance summer tips for your evergreen trees from our Evergreen Tree Low Maintenance Guide.
